1. Field of the Invention
The present invention relates to a continuously operating press for the production of particle board, fiberboard, plywood sheets and the like.
2. Discussion of Related Art
In the production of particle board, fiberboard, synthetic plastic and laminate sheets, the vulcanizing of conveyor bands, plywood sheets and the like, it is necessary to expose the material to be pressed to high pressures and temperatures, if the required quality is to be attained. The known, intermittently operating single level hot plate presses do satisfy these requirements, but their output is relatively low. Known continuously operating presses such as those disclosed in German Offenlegungsschrift No. 28 53 285 and German Patentschrift No. 198131 are intended to eliminate this disadvantage. They have the further advantage, for example, in the production of particle board that the finished product is an endless plate, which is desirable to produce uniform quality and favorable cutting proportions. In order to reduce friction between the steel bands and the table and the press tup serving as the support, the sliding surfaces facing the steel bands are composed of small rolls. It is necessary, however, to support each roll carpet over the width of the band by means of roll bodies serving as counter bearings. Otherwise the support rods would bend out of shape and the pressed surface would become uneven.
Another disadvantage of known continuously operating presses is that the supports are not only costly but that they also provide an excessively complex structure susceptible to failure. Furthermore, such a layout results in a large number of inaccessible support locations which, when damaged, lead to the shutdown of the press or even of the entire installation.
Still further, the abovementioned designs for continuously operating presses are poorly suited to effect an adequate transfer of heat to the steel bands and thus to the material being pressed, because the spaces wherein the roll and the roll bodies are arranged, act as insulators between the press table and the tup on the one hand and the steel bands on the other.